1. Field of the Invention
The present invention relates generally to implantable medical devices, and more particularly, to drug retaining surface features in an implantable medical device
2. Related Art
Medical devices having one or more implantable components, generally referred to as implantable medical devices, have provided a wide range of therapeutic benefits to patients over recent decades. Implantable medical devices often include one or more instruments, apparatus, sensors, processors, controllers or other functional components that are permanently or temporarily implanted in a patient. The implanted components are used to, for example, diagnosis, monitor, or treat a disease or injury, or to modify the patient's anatomy or a physiological process. Many of these implantable components receive energy (i.e. power and/or data) from external components that are part of, or operate in conjunction with, the implantable component. Implantable hearing prostheses that treat the hearing loss of a prosthesis recipient are one particular type of implantable medical devices that are widely used today.
Hearing loss, which may be due to many different causes, is generally of two types, conductive and sensorineural. In some cases, a person suffers from hearing loss of both types. Conductive hearing loss occurs when the normal mechanical pathways for sound to reach the cochlea, and thus the sensory hair cells therein, are impeded, for example, by damage to the ossicles. Individuals who suffer from conductive hearing loss typically have some form of residual hearing because the hair cells in the cochlea are undamaged. As a result, individuals suffering from conductive hearing loss typically receive an implantable hearing prosthesis that generates mechanical motion of the cochlea fluid. Some such hearing prosthesis, such as acoustic hearing aids, middle ear implants, etc., include one or more components implanted in the recipient, and are referred to herein as implantable hearing prosthesis.